Liquid transfer system



United States Patent O 3,490,482 LIQUID TRANSFER SYSTEM Elihu L. Sachs,930 Cranford Ave., North Woodmere,

N.Y. 11598, and Edward Mezynski, 142-02 243rd St., Rosedale, N.Y. 12472Filed Apr. 25, 1968, Ser. No. 724,114 Int. Cl. B67d 5/54; F17d 1/12;G03d 11/00 US. Cl. 137-205 16 Claims ABSTRACT OF THE DISCLOSURE A liquidtransfer system including a reservoir, a liquid utilization containerand a pair of valved conduits, one conduit adapted to provide fluid flowcommunication in both directions between the reservoir and thecontainer, the other adapted to provide fluid flow communication onlybetween the container and the reservoir, the fluid flow being effectedby a reservoir pressure varying means.

BACKGROUND This invention relates to liquid transfer systems and, moreparticularly, to film processing apparatus including a system fortransferring processing liquids from a reservoir to a film developingcontainer and, after a predetermined period of time, returning theliquid to its reservoir or other desired destination.

While liquid transfer systems and, specifically, automatic filmprocessing apparatus is presently available, there is a need forinexpensive, maintenance-free and easy to use apparatus for transferringa liquid from a reservoir to a utilization container and back to thereservoir and, where a plurality of liquids are involved, to do thesame, sequentially for each liquid. For illustration purposes only, anexample of the need for such a system is in medical and dental ofiicesfor used in developing X-ray films. A desirable system will require aminimum amount of effort by the doctor or nurse using the system andwill automatically develop the film in a minimum amount of time and witha minimum amount of supervision, while insuring proper development ofthe film.

OBJECTIVES Accordingly, it is one object of this invention to provide aliquid transfer system which is inexpensive, substantiallymaintenance-free and which requires a minimum amount of supervision,care and skill by its user.

It is another object of this invention to provide a liquid transfersystem which automatically sequentially transfers a plurality ofprocessing liquids to a liquid utilization container, allows eachprocessing liquid to remain in the container for a predetermined timeinterval, and then completely removes the liquids from the container.

A still further object of this invention is to provide a liquid transfersystem which prevents the intermixing of the several liquids employedand which avoids the flow of processing liquids through or in contactwith moving parts.

BRIEF DESCRIPTION OF ONE EMBODIMENT Briefly stated, this invention, inone form, comprises a film developing container having a sloped floorand a light-proof, vented, closure. A plurality of processing liquidsare located each within its own reservoir with each reservoir being influid flow communication with the film developing container by means ofa pair of valved conduits; i.e. a primary liquid transfer conduit and ascavenger conduit. Each reservoir is connected to a conventionalvariable pressure source which selectively subjects the reservoirs tosuper-atmospheric and subatmospheric pressure, the former being used totransfer the liquid from the reservoir to the film developing containerthrough the primary conduit and the latter being used to return theliquid to the reservoir through the primary and scavenger conduits. Thepressure source communication with each reservoir is controlled 'by asolenoid valve which is actuated by a conventional timer.

In order to develop an exposed light sensitive or X-ray sensitive filmthe operator places the film in a conventional manner into a filmdeveloping container. This first step is performed in the absence oflight other than a photographic safe light while the remainingprocessing may be performed in a normally lighted room, thus obviatingthe need for a photographic dark room. However, if a film of the typedescribed in US. Patent 3,374,352 to Dr. Elihu Sachs, the inventor ofthe present system, is used, even the loading of the film into the filmdeveloping container can be performed in normal room light. Hence, theneed for any dark room facilities will be obviated.

After closing the film developing container, the operator merely tripsthe start switch of the system and the film is then automaticallydeveloped as follows. The timer, through a timing circuit, starts thepressure source, such as an air compressor, and actuates the appropriatevalves to supply pressurized air to the appropriate reservoir containingthe processing liquid to be used initially, such as the developerliquid. The primary conduit valve, being open, permits the processingliquid to be forced through the primary conduit into the film developingcontainer while the valve in the secondary conduit, or scavenger tube,being a check valve, prevents the flow of air and liquid through thesecondary conduit to the film developing container.

After a predetermined quantity of processing liquid has been transferredto the film developing container, the valve in the primary conduitsubstantially obturates the conduit, preventing flow of substantialquantities of air through the conduit into the film developing containerbut allowing a small quantity of air to flow into the container in orderto continuously agitate the processing liquid. Means, such as a pressurerelease vent in the reservoir, also control the quantity of air whichflows into the film developing container. After the developer hasremained in the developing container for its required time period, thetimer actuates the appropriate valves such that the reservoir for theliquid in the developing container is subjected to subatmosphericpressure. The reduced pressure in the reservoir causes the liquid toflow from the film developing container through the primary andscavenger tube back to the reservoir.

The scavenger tube has a cross-sectional area significantly smaller thanthe primary conduit and has one open end adjacent the lowest point ofthe floor of the film developing container to allow it to removewhatever remaining liquid was not removed through primary conduit. Uponremoval of all developing liquid from the film developing container, thenext liquid, such as water for washing, is then caused to enter the filmdeveloping container in the same manner as described above. In sequenceeach necessary processing liquid for developing the film is admitted andremoved from the film developing container until the developing, processis complete.

DESCRIPTION OF THE DRAWINGS The objectives and advantages describedabove as well as others, and the apparatus and its operation will bebetter understood from the description below and appended drawings inwhich:

FIGURE 1 is a schematic illustration of a liquid transfer system formedin accordance with a first embodiment of this invention, and

3 FIGURE 2 is a schematic illustration of a liquid transfer systemformed in accordance with a second and preferred embodiment of thisinvention.

APPARATUS OF FIRST EMBODIMENT (FIGURE 1) Referring now to the drawings,and more particularly to FIGURE 1, there is illustrated an automaticfilm proc essing apparatus 10. The film processing apparatus basicallyincludes a film developing container 12 in fluid flow communication witha plurality of processing liquid reservoirs 14, 1 6, only two beingillustrated although it is understood that the number of reservoirs canbe one or more as required by the particular process for which thesystem is used. A pressure source, such as a conventional air compressor18 is also in flow communication with the reservoirs to allow thereservoirs to be selectively subjected to superatmospheric andsubatmospheric pressures as described below. Each reservoir and itscommunication system with the film developing container 12 is identicaland therefore the following description Will be directed to thereservoir 14 and its relationship with the film developing container 12.

The film developing container 12, which can be formed of stainlesssteel, glass, or a plastic such as polystyrene, is formed with a floor20 being sloped toward one point to insure drainage of all of the liquidtoward that low point thus facilitating removal of all liquid when sodesired. The side walls 22 of the container 12 are tapered downwardlytoward the floor 20 so that a stand 24 can easily support the container12. It is clear that other methods of supporting the container aresuitable, such as by forming a shoulder on the outer surface of thewalls against which the stand can abut. The container is provided with alight-proof closure 26 having a light-proof vent 28 of conventionalstructure and having a primary aperture 30 and secondary aperture 32therethrough to receive fluid transfer conduits.

The reservoir 14, which can also be fabricated from stainless steel,glass, or a plastic such as polystyrene, is divided into two chambers34, 36 by a divider wall 38. An aperture 40 extends through the bottomwall 42 of the reservoir 14 and receives a primary fluid transferconduit 44 which is sealed to the bottom wall by a conventional sealingplug 46. The primary conduit 44 extends from the reservoir 14 to thefilm developing container 12 and passes through the primary aperture 30in the container closure 26 to which it is also sealed by a conventionalsealing plug 48. The primary conduit 44 terminates adjacent to the floor20 of the container 12.

' A cylindrical elongated valve housing 50 is received at one end by theend of the primary conduit 44 which has entered the reservoir 14 and, atits other end, passes through an aperture 52 in the reservoir dividerwall 38. The valve housing 50 has a first primary orifice 54 through itsupper end which provides flow communication between the inside of thehousing 50 and the reservoi rs first chamber 34. The housing 50 has asecond primary orifice 56 through its lower end which provides flowcommunication between the housing and the primary conduit 44. Aplurality of secondary orifices 58 extend through the side wall 60 ofthe housing and provide flow communication between the inside of thehousing and the reservoirs second chamber 36. In order to force liquidin the chamber 34 to flow into the housing 50, the divider wall 38 istapered toward the first primary orifice 54.

The housing 50 is tapered at its upper and lower ends in order toprovide a seat at each end for a floating ball valve 62 confined withinthe housing 50. The ball valve 62 floats in the processing liquidcontained within the reservoir 14 and is responsive to the height of theliquid such that when the liquid rises to a certain height within thereservoir 14 the ball valve 62 obturates the first primary orifice 54and, when the level of the processing liquid drops to a predeterminedlevel, the ball valve 62 obturates the second primary orifice 56. Themethod and purpose of operation of the ball valve 62 are described indetail below.

A secondary or scavenger conduit or tube 64 extends through an aperture66 in one of the walls, for example the top wall, of the reservoir 14and communicates with the first chamber 34. The other end of thescavenger tube 64 passes through the secondary aperture 32 in theclosure 26 of the film developing container 12 and terminates adjacentto the floor 20 at the lowest point of the floor. As with the primaryconduit 44, the scavenger tube is appropriately sealed to the filmdeveloping container 12 and reservoir 14. A check valve, such as aflapper valve 68, is located within the scavenger tube to permit fiow inonly one direction, that direction being from the film developingcontainer 12 to the first chamber 34 of the reservoir 14. The scavengertube 64 has a cross-sectional area significantly smaller than theprimary conduit 44 to enable it to remove all of the liquid remaining inthe film developing container 12 which was not removed through theprimary conduit 44. It has been found that a system having a 1" primaryconduit and a scavenger tube is satisfactory. The end of the scavengerconduit 64 which is adjacent to the floor 20 of the container 12 isprovided with a tapered nose 70 to facilitate removal of all liquid fromthe container 12.

LIQUID TRANSFERRING MEANS In order to cause the liquid in the reservoir14 to flow from the reservoir to the container 12 and, after the liquidhas remained in the container for its necessary time interval, to causethe liquid to return to the reservoir 14 an inexpensive source ofpressure, such as a conventional air compressor 18, is provided. Boththe high pressure side 72 and the low pressure side 74 of the compressor18 are placed in flow communication with the first chamber 34 of thereservoir 14 by means of an air transfer duct 76.

Since it is intended to selectively subject the reservoirs tosuperatmospheric and subatmospheric pressures through use of thecompressor 18 it is necessary to provide valve means to selectivelyexpose either the high pressure side 72 or the low pressure side 74 ofthe compressor to the reservoirs and to vent the side not exposed to thereservoirs. Accordingly, vents 78, are provided on the high pressure andlow pressure sides respectively of the compressor 18. Remote controlvalves 82, 84, such as common electrically operated solenoid valves, arelocated at the juncture of the vents and the conduits leading to the airtransfer duct 76. The valves are three-way valves which either permitfluid flow communication between the compressor 18 and the air transferduct 76 or between the compressor and the appro prlate vent. The airtransfer duct 76 is connected through branch pipes 86 to each of thefirst chambers 34 of the reservoirs 14, 16, etc. with each branch pipe86 having an electrically operated solenoid valve 88 in the line toselectively expose the appropriate reservoir to the pressure source,that is, the compressor 18.

OPERATION OF SYSTEM To utilize the film processing apparatus 10, theoperator merely closes a start switch 89 which, through a standard typeof timing circuit, shown schematically at 90, actuates a solenoid toopen the valve 88 leading to the first chamber 34 of the reservoir 14.The solenoid operating the valve 84 at the low pressure side 74 of theair compressor 18 is also activated to provide communication between thelow pressure side 74 and the atmosphere through the vent 80. Valve 82 onthe high pressure side 72 of the compressor is positioned to close thevent 78 and provide flow communication between the compressor 18 and theair transfer duct 76. The compressor 18 is started and air, pressurizedto approx imately 30 p.s.i.a., is pumped through the duct 76 into thefirst chamber 34.

The high pressure present in the first chamber 34 closes the check valve68 in the scavenger tube 64 and forces the processing liquid into thefilm developing container 12 through the primary conduit 44. After apredetermined quantity of processing liquid has been transferred to thecontainer 12, the ball valve 62 substantially closes the second primaryorifice 56 permitting a small quantity of air to be pumped through theprimary conduit 44 into the container 12. The air passing through theprimary conduit continuously agitates the liquid in the container andprevents the primary conduit from serving as a siphon. The pressure inthe reservoir 14 is prevented from exceeding a predetermined level by apressure relief bypass 91 extending from the air transfer duct 76 intothe container 12. A spring-biased check valve 92 in the bypass preventsliquid from flowing through the bypass when subatrnospheric pressureexists in the air transfer duct 76. Furthermore, the valve is set toopen at a pressure in excess of the normal pumping pressure to permitbleedoif.

After a predetermined period of time, the period depending upon the timerequired for treatment of the film by the particular processing liquidwhich resides in the container 12, the timing circuit actuates valve 82on the high pressure side of the compressor 18 to provide communicationbetween the compressor and the vent 78 and, simultaneously, valve 84 isoperated to close vent 80 and provide communication between the airtransfer duct 76 and the low pressure side 74 of the compressor 18.Continuous operation of the compressor will reduce the pressure in thereservoir 14 to subatmospheric pressure, approximately 5 p.s.i.a., inorder to effect transfer of the liquid from the film developingcontainer 12 to the reservoir 14 through both the primary conduit 44 andthe scavenger conduit 64. After substantially all of the liquid isremoved from the film developing container 12 the ball valve 62, whichhas risen toward the top of the housing 50, obturates the first primaryorifice 54 and the remaining liquid in the container 12 is removedthrough the scavenger tube 64. The ball valve 62 prevents the drawing ofair from the container 12 into the reservoir 14 through the primaryconduit 44 which, if such were allowed to occur, would reduce thepressure differential across the scavenger conduit 64 rendering itdifiicult to remove the remaining liquid in the container 12. Removal ofall the liquid from the container 12 will be performed in a measuredtime interval after which the timing circuit will effect discontinuanceof operation of the air compressor 18 and actuation of the solenoidvalve 88 terminating communication between the reservoir 14 and the airtransfer duct 76. The pressure in the reservoir then will rise toatmospheric pressure by virtue of the open passageway through thescavenger conduit.

If a plurality of processing liquids and, hence, reservoirs are employedthe timing circuit sequentially opens the valve between the air transferduct 76 and the next reservoir to be utilized such as reservoir 16, andthe liquid transfer procedure described above is repeated until all ofthe required liquids have performed their function in the filmdeveloping container.

APPARATUS OF SECOND (PREFERRED) EMBODIMENT (FIGURE 2) The second andpreferred embodiment 100 illustrated in FIGURE 2 operates on the sameprinciple as the first embodiment (FIGURE 1); however, it includesseveral modifications and improvements.

The processing liquid reservoir 102 is cylindrical in form and includestapered upper and lower ends 104, 106

respectively. The upper end 104 is provided with a first, 3

bell mouthed, chamber 108 which communicates in funnel fashion with themain chamber 110 of the reservoir 102. The main chamber is divided intotwo sections 112, 114 by a perforated member such as a screen 116. Apair of ball valves 118, is placed in the main chamber 110, one ballvalve 118 inthe upper section 112 and one ball valve 120 in the lowersection 114. The ball valves 118, 120 have a diameter larger than theapertures 122, 124 through the upper and lower ends 104, 106,respectively, of the main chamber 110.

A primary fluid transfer conduit 126 is connected near one end to thelower end 106 of the reservoir 102 and at its other end it extends downinto a film developing container 128. A drainage valve 129 is providedto allow for cleaning of the reservoir 102. A scavenger tube 130,extending from the film developing container 128 into the bell mouthedchamber 108, has a check valve 132 to 1 permit flow only from the filmdeveloping container 128 toward the reservoir 102. Also mounted in flowcommunication with the bell mouthed chamber 108 is an air transfer duct134 which connects the chamber 108 with a compressor 136. The pressuresource and control system is the same as discussed above with respect tothe first embodiment.

A thermostatically controlled heater 138 is mounted in the reservoir 102to maintain the processing liquid stored therein at a constanttemperature.

The film developing container 128 is essentially the same as describedabove and illustrated in FIGURE 1; however, it includes a fresh rinsewater supply and drain to improve the film washing. A water supply pipe140, attached at its remote end to a fresh water supply (not shown), andhaving a remote-controlled valve 142 therein opens into the top of thecontainer 128. A drain pipe 144, having its inlet end 146 near thebottom of the container 128, empties into a drainage system, such as asink. The drain pipe 144 leaves the container 128 near the top thereofand serves as an overflow drain to permit rinse water from the supplypipe to continually flow during the film wash cycle. In addition to thiscontinuous Water supply and overflow drain, a water reservoir with aprimary conduit and scavenger tube are also used to insure quick fillingand complete emptying of the developing container 128.

CHEMICAL INJECTION SYSTEM Another modification of this preferredembodiment is the addition of a chemical injection system 148 whichprovides for the introduction of a small measured quantity of a chemicalsolution into the developing container 128 at an appropriate time. Forexample, it is desirable, during the final wash cycle, to introducecertain solutions called hypoeliminators in order to reduce the washingtime from fifteen minutes to about one and one-half minutes. Othersolutions which might be added in this way are short-stop, hardner andwetting agents, all of which are conventional in film developing and donot, of themselves, form a part of this invention.

Each chemical solution is stored in a reservoir, for example, reservoir150. A supply conduit 152 leads from the reservoir to the developingcontainer 128 and an air transfer duct 154, having a remote controlvalve 156, connects the reservoir 150 with the high pressure side of thecompressor 136. When the chemical solutions are added during wash cyclesthere is no need to have a scavenger tube to return the solution to thereservoir. However, when the solution is used independent of a wash, areturn flow system, including a scavenger tube, can be provided in themanner discussed above with reference to reservoir 102. A heater 158also can be utilized if so desired.

reservoir 102 and force the processing liquid into the film developingcontainer 128. After the liquid level drops to a predetermined level theball valve 120 substantially obturates the aperture 124 allowing only asmall quantity of air to flow into the developing container 128 foragitation purposes. The ball valve 120 should be heavy enough to preventthe air entering the reservoir from dislodging the ball valve from theaperture 124. It has been found that a ball valve having a specificgravity of about 0.9 is satisfactory.

After the processing liquid has remained in the developing container 128for a predetermined time period the timing circuit 160 effects openingand closing of appropriate valves (for details see discussion of firstem- 'bodiment) to subject the reservoir 102 to subatmospheric pressureresulting in removal of the processing liquid from the container 128.After most of the liquid has been transferred back to the reservoir, theliquid level will be such as to cause ball valve 118 to obturate theaperture 122, divorcing the primary conduit 126 from the reducedpressure and applying the pressure differential across the scavengertube 130 for complete removal of the liquid. Use of the two ball valves118, 120 and screen member 116 avoids the need for a valve housing, suchas housing 50 of FIGURE 1.

When a wash cycle is needed, the reservoir (not shown) containing washwater is pressurized and the above operation is repeated. In addition,the fresh water supply valve 142 is opened providing continuous supplyof fresh water. When the water level reaches the highest point on thedrain pipe, an overflow system is effected. It should be clear that thehighest point on the drain pipe must be below the highest point on theprimary conduit and scavenger tubes to prevent Water from flowing intothe processing liquid reservoirs.

When it is desired to inject a chemical solution, such as ahypoeliminator into the developing container 128 the timing circuiteffects opening of valve 156 in the air transfer duct 154. A measuredquantity of chemical solution injected and control of this quantityinjected is through time control of the valve 156. If the chemicalsolution is injected into rinse water, water supply valve 142 is closeduntil the solution has remained in the container 128 for its requiredacting time. Then the solution is removed with the rinse Water.

While the first and second embodiments are shown and describedindividually it is clear that any of the features of either embodimentcan be used with the other embodiment.

It will thus be seen and appreciated that the liquid transfer system ofthis invention requires no skill to operate and a minimum amount ofsupervision, the only time required being for loading of the film intothe film developing container 12 and for actuating the timing circuit.The rest of the developing process occurs automatically without the needfor the presence or attention of an operator. The only moving partswhich come in contact with the processing liquids, which are corrosive,are the floating ball valves which can be made of a plastic, such aspolyethylene, which is resistant to these chemicals. Thus, themaintenance problem is minimal with the only primary maintenance beingthe changing of the processing liquids after they have been used acertain number of times, the frequency of change being determined by thetype and frequency of use of the processing liquids. The apparatus isalso very expensive since the liquid utilization container, thereservoirs, the primary and scavenger conduits, the ball valve and itshousing, and the rest of the valves can all be made of inexpensivematerial. The air compressor, being a relatively low pressure aircompressor, capable of providing pressures up to 30 p.s.i.a. is alsoinexpensive. Each of the parts can be replaced easily thereby reducingthe down time in the event of a malfunction of any part of the system.All of this is extremely important in'certain areas of use, such as indoctors and dentists Offices where X-rays are constantly being taken andmust be developed with a minimum of time and attention and by someonewho usually has little or no knoweldge and experience in the field offilm developing, such as a nurse or doctor. The need for a photographicdarkroom is also eliminated since the only period of time in which theroom must be dark is during loading of the film into the film developingcontainer, and this can be eliminated by using a film of the typedescribed in U.S. Patent 3,374,352.

What is claimed as new and desired to be secured by Letters Patent ofthe United States is:

1. A liquid transfer system comprising a reservoir, a liquid utilizationcontainer, a primary and a secondary conduit each adapted to providefluid flow communication between said reservoir and said container,means for effecting transfer of a liquid between said reservoir and saidcontainer, primary valve means adapted to minimize fluid flow throughsaid primary conduit upon transfer of a predetermined quantity of theliquid between said reservoir and said container, said secondary conduithaving a cross sectional area smaller than the cross sectional area ofprimary conduit and having an open end adjacent to the floor of saidcontainer.

2. A system as defined in claim 1 wherein the means for effectingtransfer of the liquid includes means for selectively subjecting saidreservoir to superatmospheric and subatmospheric pressure.

3. A system as defined in claim 1 wherein said valve means isliquid-quantity responsive.

4. A system as defined in claim 1 wherein said valve means is responsiveto the height of liquid present in said reservoir.

5. A system as defined in claim 2 including secondary valve meansadapted to permit flow in one direction through said secondary conduit,said direction being from said container to said reservoir.

6. A system as defined in claim 5 wherein said primary valve meansminimize gas flow through said pri mary conduit,

(a) from said reservoir to said container upon con1- pletion of thetransfer of a predetermined quantity of said liquid from said reservoirto said container,

(b) from said container to said reservoir upon completion of thetransfer of a predetermined quantity of said liquid from said containerto said reservoir.

7. A system as defined in claim 5 wherein said reservoir comprises afirst and a second chamber, said means for effecting transfer of theliquid and said secondary conduit communicating with said first chamber.

8. A system as defined in claim 7 wherein said primary valve meansincludes a valve housing, said housing having a first primary orificeproviding flow communi cation between said housing and said firstchamber, a second primary orifice providing flow communication betweensaid primary conduit and said housing, and at least one secondaryorifice providing flow communication between said housing and saidsecond chamber.

9. A system as defined in claim 8 including a ball valve confined withinsaid housing, said ball valve (a) substantially obturating said firstprimary orifice upon completion of the transfer of a predeterminedquantity of said liquid from said container to said reservoir, and

(b) substantially obturating said second primary orifice upon completionof the transfer of a predetermined quantity of said liquid from saidreservoir to said container.

10. A system as defined in claim 7 wherein the floor of said containeris sloped downwardly and wherein said secondary conduit has an open endadjacent the lowest part of said floor.

11. Film processing apparatus comprising:

(a) a processing liquid reservoir having a first and a second chamber,

(b) a film developing container,

(c) a primary conduit providing fluid flow communication between saidreservoir and said container,

(d) a secondary conduit providing fluid flow communication between saidfirst chamber and said container, said secondary conduit having an openend adjacent to the floor of said container and having a cross-sectionalarea smaller than the crosssectional area of said primary conduit,

(e) means for selectively subjecting said first chamber tosuperatmospheric and subatrnospheric pressure to effect, respectively,transfer of the liquid from said reservoir to said container and fromsaid container to said reservoir,

(f) primary valve means, responsive to the quantity of liquid present insaid reservoir, adapted to minimize fluid flow through said primaryconduit upon transfer of a predetermined quantity of the liquid betweensaid reservoir and said container, and

(g) secondary valve means adapted to permit flow in one directionthrough said secondary conduit, said direction being from said containerto said reservoir.

12. Apparatus as defined in claim 11 wherein said reservoir includes (a)a second chamber having a tapered upper end and a tapered lower end,each of said ends having an aperture therethrough; and said primaryconduit being mounted on said lower end,

(b) a perforated member dividing said second chamber into upper andlower portions,

(c) a first chamber having a tapered lower end in flow communicationwith the upper end of said second chamber and wherein said primary valvemeans include (d) a ball valve in each of said upper and lower portionsof said second chamber.

13. Apparatus as defined in claim 6 including a valved fresh watersupply pipe and an overflow drain, the highest point of said overflowdrain being below the highest point of said primary and secondaryconduits 14. Apparatus as defined in claim 11 including a chemicalinjection system, said injection system including (a) a chemicalreservoir,

(b) a chemical supply conduit providing fluid flow communication betweensaid chemical reservoir and said containers and (c) means for subjectingsaid chemical reservoir to superatmospheric pressure to effect transferof the chemical to said container.

15. Apparatus as defined in claim 11 including a plurality of saidreservoirs each having a primary and secondary conduit in fluid flowcommunication with said container and wherein the means for pressurizingand depressurizing said first chamber includes valve means whichsequentially subjects each reservoir in a predetermined order tosuperatmospheric pressure and then subatmospheric pressure and whereinsaid valve means is responsive to time intervals whereby said containersequentially contains a plurality of liquids in a predetermined order.

16. Apparatus as defined in claim 12 including a plurality of saidreservoirs each having a primary and secondary conduit in fluid flowcommunication with said container and wherein the means for pressurizingand depressurizing said first chamber includes automatically operated,time controlled valve means which sequentially subjects each reservoirin a predetermined order to superatmospheric pressure and thensubatmospheric pressure whereby said containers sequentially contain aplurality of liquids in a predetermined order.

References Cited UNITED STATES PATENTS 3,252,478 5/1966 Limberger137571X ALAN COHAN, Primary Examiner U.S. C1.X.R.

UMTJ'LD S'IAIPLS IAlEN'i. OFFICE CERTIFICATE OF CORRECTION Patent No.3390 4322 Dated Jgn 20, 1970 Inventor(s) ELIHU L. SACHS and EDWARDMEZYNSKI It is certified that error appears in the above-identifiedpatent and that said Letters Patent are hereby corrected as shown below:

Column 2, line 55, after "through" insert --the--;

SIGNED AND SEALED JUN 2 3197 (S Amen mm win-1m 2:. sum JR- Atteit gOffim l Gomissioner of Paton"

